1. Field of the Invention
The present invention generally relates to a wireless power transfer, and the present invention particularly relates to a system and a method for detecting an object on a power transfer path of a wireless power transfer.
2. Background of the Invention
A small power device includes a consumer and an accumulator in order to allow for wireless utilization. To charge the accumulator, power may be transferred wirelessly from a power supply to the small device by using an electromagnetic field to transfer power. For this purpose, the power supply and the small device each include a coil, the coils being positioned at a small distance from one another and thus essentially together forming a transformer.
If an electrically conductive object gets into the area of the electromagnetic field, eddy currents may form which heat the object. If the object is magnetizable, the object may also be heated through core or hysteresis losses. The heating may be considerable, so that an operational reliability of the transmitter or of the receiver cannot be ensured. Moreover, the object may withdraw power from the electromagnetic field, so that the power transfer to the receiver is interfered with.
It is possible to detect the presence of the object by determining the influence of the object on the inductance of the transmitter coil. If, however, the object is relatively small or relatively far away from the transmitting coil, it may be difficult to reliably detect the object.
The object underlying the present invention is therefore to provide a system, a method, and a computer program product, with the aid of which a preferably precise, reliable, and highly sensitive determination of the object may be carried out, in order to enable a response to the presence of the object. The present invention achieves the objects indicated above with the aid of a power transfer system, a method, and a computer program product.